I need to film my son's school play. The school sell DVDs and raises money. I have access to a couple of Canon 5d Mk3s which will provide amazing video quality, BUT they will only film for a maximum of 30 minutes. I can't stop and start it as I will miss a section of the play. I want to have one camera set up to film the whole stage and then another that I can use for close ups. But the 30 minute limitation makes this a pain - not to mention the ideal of having one continuous audio track as a reference for syncing the editing. Are there any still cameras that will film until they run out of memory (like a go-pro for example)? Or is there a way of removing the limitation from the 5d3 ?